Jena announce

Jena accepted by the Apache Incubator

2010-11-28T15:58:00.000Z

Jena has been accepted into the Apache incubator. That's the easy part - now we have to sort out the legal side, migrate the codebase and set up the new project infrastructure. This can take some time.

This does not mean we're not doing the usual releases. We will continue to release Jena and it's related components as non-Apache releases in parallel.

The proposal we made can be found at: http://wiki.apache.org/incubator/JenaProposal

Jena at SemTech 2010

2010-06-02T14:27:00.000+01:00

For those of you going to SemTech in San Francisco at the end of June, there is a chance to meet up to discuss Jena and things you have done with it.

This will be on the afternoon of Wednesday June 23rd, starting at 15.15

If you would like to include a demo or presentation about work you have done with Jena please let us know (mailto:semtech@openjena.org), with a brief description of what you like to present. Please indicate whether a five minute or twenty minute slot would be more appropriate.

This is intended to be informal and easy-going- there wil also be plenty of time for discussions and meeting Jena users and Jena developers.

Releases Jena 2.6.3, ARQ 2.8.4 and TDB 0.8.6

2010-06-02T14:23:00.000+01:00

This is the first release of the Jena main distribution, after the majoritiy of the developers time at HP.

As we move forward as an independent open source project, we are always looking for contributions: send them to the patch tracker on SourceForge.

They are also available from the central Maven repository and our own:

Jena maven repository

For snapshots, we also have a development repository:

Jena development maven repository

OpenJena

2009-10-22T11:10:00.002+01:00

The Jena platform will become an independent open source project from the end of October. Many current members of the Jena team will remain involved in further enhancements to the Jena codebase, including supporting the user community such as jena-dev mailing list.

We have a new server

http://openjena.org/

The server is kindly provided by Talis for which we are very grateful.

The code will remain licensed under a BSD-style license and, with HP's support and assistance, we are in discussions to transfer the copyright to a neutral, non-profit, organisation.

The development process remains on SourceForge, including the main download area and development CVS and SVN repositories. The change to an independent open source project will enable us to continue and expand the core developer community, and will make it easier to accept contributions through the SourceForge patches tracker. The main download area and development CVS and SVN repositories remain on SourceForge. We have no plans to change the package naming, aiming to minimise any changes to Jena users.

We would like to thank all of the various customers, users, research groups and individual contributors we have worked with over the years as we have built the Jena platform to its current state and hope we will continue working togther as the project moves to a new phase. We look forward to future enhancements to Jena's capability, and to helping to create other exciting developments in Semantic Web technologies and products.

The Jena Team

New releases: Jena 2.6.2 and ARQ 2.8.1

2009-10-22T11:00:00.004+01:00

New releases of Jena and ARQ are available: these are primarily maintenance releases but do use a new build system.

They are also available from our Maven repository

Jena maven repository

You only need to download one of these to get jars. The Jena
distribution contains the source, javadoc and test materials for Jena;
the ARQ distribution contains the source, javadoc and test materials for
ARQ.

Releases: SDB 1.3.0 and TDB 0.8.1

2009-06-22T22:43:00.004+01:00

New releases, compatible with Jena 2.6.0:

Both are avilable from the Jena development maven repository.

Note that TDB 0.8 is not compatible with TDB 0.7.X - there is a TDB 0.7.6 release that is the same as TDB 0.8.1 except it is compatible with all TDB 0.7 releases.

New releases: Jena 2.6.0 and ARQ 2.7.0

2009-05-25T20:00:00.004+01:00

These releases move Jena to using Java 5 and, in particular, Java generics, both internally and in the application APIs. We have also cleared out many deprecated features, switched to using SLF4J as the logging wrapper and reduced the number of jars by using features of Java 5.

There is also a RC release of TDB 0.8.0 which uses this upgraded Jena. Caveat: the file format for TDB 0.8 is different to that for TDB 0.7.x and earlier.

Release: TDB 0.7

2009-01-19T14:02:00.002Z

Download: TDB 0.7.1
TDB Documentation

TDB 0.7 introduces new features:

Named graph support - Native TDB support for RDF datasets
Persistent RDF namespace prefixes
Reification: Support for Reification style standard

The code is also available via maven and Apache ant/ivy:

Repository: http://jena.hpl.hp.com/repo-dev/
GroupId/Org: com.hp.hpl.jena
ArtifactId/Name: tdb

In addition, there has been significant internal changes to prepare for future work. Performance testing of the new architecture shows that when used the same way as 0.6, TDB performs at the same speed.

Named graphs are not as fast to load as the default graph in the dataset.

New release: SDB 1.2

2009-01-19T14:00:00.001Z

Download: SDB 1.2.0
SDB Documentation

SDB 1.2 is primarily a maintenance release. It does include support for MS SQL Server 2008

There are no changes to the database schemas.

The code is also available via maven and Apache ant/ivy:

Repository: http://jena.hpl.hp.com/repo/
GroupId/Org: com.hp.hpl.jena
ArtifactId/Name: sdb

New Release: Eyeball 2.1

2008-12-22T17:40:00.001Z

Chris has announced a new version of Eyeball. Eyeball is a tool for detecting problems with RDF data: misconstructed URIs, classes and properties with no definition, mis-spelled literals, etc. Eyeball is extensible: you can write your own Inspectors and have Eyeball apply them to your data.

Jena 2.5.7, ARQ 2.6.0

2008-12-19T20:08:00.004Z

This is a linked release - Jena 2.5.7 contains ARQ 2.6.,0 and ARQ 2.6.0 ships with the jars for Jena 2.5.7. The difference is mainly the source code included.

New Release: ARQ 2.5 and TDB 0.6

2008-10-28T22:21:00.004Z

This release of TDB introduces a statistics based optimizer for filtered basic graph patterns.

The release of ARQ is coupled with the release of TDB to provide enhanced integration into the query execution process for custom storage layers. It also provides any bug fixes done since the last release.

New releases: ARQ 2.4, Joseki 3.2, TDB 0.5

2008-08-09T13:23:00.006+01:00

The release of ARQ 2.4 introduces property paths. It also includes some internal simplification for making extensions to ARQ at the basic graph pattern level (a defined extension point for SPARQL) for different storage and logic engines. This simplified extension for basic graph pattern matching is used by TDB 0.5.

This is the first release for TDB. Documentation on the TDB wiki.

The release of Joseki 3.2 is an accumulation of many improvements since version 3.1. Some of these make the use of SDB and TDB with Joseki possible with the released version, not just with development CVS.

New releases: Jena 2.5.6, ARQ 2.3 and SDB 1.1

2008-06-12T10:16:00.003+01:00

A common theme in these releases is improvements in the implementations of SPARQL/Update and extending it with a first-release implementation for SDB. The extended SPARQL also includes two ARQ extensions for assignment and sub-query.

Jena available via Maven

2008-02-26T13:51:00.001Z

Jena is available as Maven artifacts. The Jena repository for released versions is http://jena.hpl.hp.com/repo and this is synchronized with the central Maven2 repository as http://repo1.maven.org/maven2/com/hp/hpl/. The artifacts include Jena and ARQ jar files, the Jena IRI library and associated software used by Jena which is distributed in source form.

Jena 2.5.5 and ARQ 2.2

2008-02-19T19:40:00.002Z

There are new releases of Jena and ARQ:

The versions of ARQ in the Jena download and version of Jena in the ARQ download are sync'ed to these releases. You only need download one of them to get the jars for both new versions. The different downloads contain different additional material such as source code.

SDB 1.0

2007-12-07T15:08:00.000Z

SDB is a SPARQL database subsystem for Jena. It provides for large scale storage and query of RDF datasets using conventional SQL databases. The database tools for load balancing, security, clustering, backup and administration can all be used to manage the installation.

Supported databases:

Oracle, 10gR2 & 11g including Oracle Express
IBM DB2 9 including DB Express
Microsoft SQL Server 2005 including SQL Server Express
PostgreSQL v8
MySQL 5.0 (>=5.0.22)
HSQLDB 1.8
Apache Derby 10.2

Download: http://downloads.sourceforge.net/jena/sdb-1.0.zip

Homepage:http://jena.sf.net/SDB

Documentation: http://jena.hpl.hp.com/wiki/SDB

We are actively seeking feedback on SDB - both good and bad. If it works, please tell us - if it doesn't work, please tell us!

Jena 2.5.4 and ARQ 2.1

2007-09-19T21:18:00.000+01:00

There are new releases of Jena and ARQ:

This is a co-ordinated release because this version of Jena introduces some low-level features that work with ARQ query planning to optimize the performance of large in-memory graph query.

The versions of ARQ in the Jena download and version of Jena in the ARQ download are sync'ed to these releases. You only need download one of them to get both new versions.

Also new in ARQ 2.1, as SPARQL extensions:

GROUP BY and Counting
The SERVICE keyword - call-out to another query service

ARQ 2.1 beta

2007-08-22T21:04:00.000+01:00

The main feature of this release is the introduction of a cost-based optimizer for in-memory basic graph patterns. For queries that involve a large amount of searching of possibilities, the optimizer can greatly improve execution times by choosing the best order in which to execute the triple patterns in a basic graph pattern. The estimation is based on statistics that the underlying store has gathered but the framework also provides for the statistics gathered by studying the dataset itself to produce more detailed statistics. The optimizer is developed by Markus Stocker.

Jena tutorial on DevX

2007-07-22T23:34:00.000+01:00

DevX have published an introductory tutorial on Jena's Model abstraction.

del.icio.us: jena, programming, semantic-web, tutorial

Jena User Conference: call for participation

2007-07-14T13:24:00.000+01:00

Registration is open for the 2007 Jena User Conference. Early registration actually closes today, but normal registration remains open for a few more weeks yet. Please note the deadline of August 1st for all registrations, which we need in order that we can give firm numbers to the hosting venue.

SDB Beta 1

2007-07-08T12:53:00.000+01:00

In this release:

support for named graphs
included support for Oracle 10gR2, including Oracle Express

Download: http://downloads.sourceforge.net/jena/SDB-0.0-beta-1.zip

Homepage: http://jena.sf.net/SDB

Documentation: http://jena.hpl.hp.com/wiki/SDB

Databases supported are now:

Oracle 10gR2 including Oracle Express
Microsoft SQL Server 2005 including SQL Server Express
PostgreSQL v8
MySQL 5.0 (>=5.0.22)
HSQLDB 1.8
Apache Derby 10.2

Microsoft SQL server 2000 has been reported to work as well.

New Release: Jena 2.5.3

2007-06-21T14:44:00.000+01:00

We've announced another maintenance release of Jena 2.5.

Jena User Conference 2007: submission deadline extended

2007-05-08T16:40:00.000+01:00

The submission deadline for the 2007 Jena User Conference has been extended to May 27th 2007. So, plenty of extra time to get those Jena position papers put together ... noting that only two page abstracts are needed for the submissions process.

Announcement: Second Jena User Conference

2007-03-20T14:56:00.000Z

We're pleased to announce the 2007 Jena User Conference, to be held in Palo Alto, California on September 5th and 6th. Chris posted the details earlier today. Submissions are now invited for papers and demos to be presented at the conference. Last year's user conference was a lot of fun, this year we're hoping for bigger and better!

del.icio.us: semanticweb, jena, conference, cfp

New releases: Jena 2.5.2 and SPARQL DB

2007-02-07T21:56:00.000Z

We've announced another bug-fix release of Jena 2.5, this time to fix a problem with listInstances() in composite OntModels, and a user-reported memory leak in the database. The updated version, release 2.5.2, is available from SourceForge in the usual way.

More exciting, Andy has released the first alpha-test version of SDB, a new persistent triplestore design, optimised for SPARQL queries. See his announcement about SDB for details.

del.icio.us: jena, semanticweb, java.

Announcing Jena 2.5

2007-01-18T17:19:00.000Z

Andy posted the message today announcing Jena release 2.5. This is primarily a maintenance release, but significant changes are afoot in the database support. See the release notes for details.

This Jena release is accompanied by the 1.5 release of ARQ, which includes free-text search. See the change log for details.

del.icio.us: jena, semanticweb, java, open-source.

New capabilities: Eyeball online, and DARQ

2006-09-07T13:47:00.000+01:00

Two very good pieces of work to report from our intern programme. Peter Coetzee, working with Chris, has announced an on-line version of the Eyeball heuristic RDF checker. And Bastian Quilitz, working with Andy, has developed DARQ: a version of ARQ that handles distributed queries across federated triple stores. Well done to all concerned!

Del.icio.us: jena, semanticweb, rdf, java, open-source

Jena conference: slides, papers and photos

2006-05-17T11:06:00.000+01:00

We've posted the papers and slides, and some photos on-line. Thanks to all who made the 2006 conference a successful event.

2006 Jena User Conference - schedule

2006-04-13T09:22:00.000+01:00

The reviews have been collated, submissions accepted, and we've now published the preliminary programme for the 2006 Jena User Conference. Preliminary just means that the order of sessions may get tweaked a bit, but the papers, demos and tutorials listed are those that will be presented. It's a varied and interesting programme, and should be great fun. Thanks and kudos to all the members of the programme committee for their hard work reviewing the submissions.

JUC programme update

2006-04-03T14:15:00.000+01:00

I've been remiss in not giving an update about the state of the programme for the Jena User Confererence, and I've had a few questions about it. The current state is that we're still reviewing a gratifyingly large collection of submissions. The deadline for submissions was extended, so we had to extend the review period as well. All being well, we'll have a preliminary programme to publish, and give feedback to submitters, on the 12th of April.

ARQ 1.3

2006-03-14T18:09:00.000Z

ARQ 1.3 has been released - this includes support for the JSON output format for SPARQL results.

The version of Joseki in CVS includes support for JSON output and SPARQLer is running that code.

SPARQLer now has a SPARQL query validation service. I found that many uses of the SPARQLer query forms seemed to be for testing query syntax so providing a better interface seemed like a good idea.

2006 Jena User Conference - registrations open

2006-02-28T15:38:00.000Z

We have added a registration form for the Jena User Conference.

Pre-registration is required for everyone planning to attend the conference, as we won't have an on-site registration facility.

2006 Jena User Conference- submission deadline extended

2006-02-20T10:06:00.000Z

We've received some requests to extend the deadline for submissionsto the Jena User Conference. Accordingly, the new deadine is March 1st, 2006.

Jena at Semantic Technology conference

2006-01-26T10:10:00.000Z

Dave and I will be presenting a Jena tutorial at the Semantic Technology Conference in San Jose, CA, on March 6th. The organizers encourage presenters not to just use such opportunities as a platform to promote their product. So, even though Jena isn't a product in the commercial sense, we've designed the tutorial around the practical aspects of developing a semantic web application in general, but using Jena as the basis. Should be fun!

New release of Eyeball

2006-01-26T10:06:00.000Z

Chris has announced a new release of Eyeball, a tool for lint-like checking of common errors in RDF and OWL documents.

ARQ 1.2

2006-01-04T10:15:00.000Z

ARQ 1.2 has been released.

ARQ 1.2 Download

ARQ web site

One new feature of note is the introduction of property functions where some arbitrary piece of code is used to calculate matches. A use of this is getting the elements in an RDF list which is rather hard in SPARQL otherwise. Property Functions

list:member - access the members of an RDF list.
rdfs:member - access the members of rdf:Bag, rdf:Seq and rdf:Alt structures

Full Extension documentation

Normally, the unit of matching in ARQ is the basic graph pattern (a sequence of triple patterns). These sets of triple patterns are dispatched to Jena for matching by Jena's graph-level query handler. Each kind of storage provides the appropriate query handler. For example, the database fastpath is a translation of a set of triple patterns into a single SQL query involving joins. There is also a default implementation that works by using plain graph find (a triple with wildcards) so a new storage system does not need to provide it's own query handler until it wants to exploit some feature of the storage. If a magic property is encountered, then it internally treated as a call to be an extension. There is a registry of property to implementing code.

# Find all the members of a list (RDF collection)
PREFIX  list:   <http://www.jena.hpl.hp.com/ARQ/list#>
SELECT ?member
{ ?x :p ?list .
?list list:member ?member .
}

The functionality of list:member is handled by a class in the extension library so this query is treated much like:

# Find all the members of a list (RDF collection)
PREFIX  ext: <java:com.hp.hpl.jena.query.extension.library.>
SELECT ?member
{ ?x :p ?list .
EXT ext:list(?list, ?x)
}

where ext:list is a function that bind its arguments (unlike a FILTER function).

So, this mechanism shows that collection access can be done in SPARQL without resorting to handling told blank nodes. cwm (which is a forward chaining rules engine) and Euler (which is a backward-chaining rules engine) already provide this style of access. Their property is - the subject and object meanings are the other way. ARQ provides list:member to be like rdfs:member. — Andy

ARQ 1.1

2005-11-23T18:09:00.000Z

ARQ 1.1 has been released - this is primarily a maintenance release but includes alignment to the current SPARQL editors' working draft. This includes support for xsd:decimal and for arbitrary precision integers.
ARQ 1.1 download

New SQL Server driver for Jena

2005-11-18T12:58:00.000Z

Dave has added an updated driver providing support for Microsoft SQL Server as a back-end for Jena persistent models. It's available for testing from CVS now, and should be released in the next Jena rev. See the announcement on jena-dev.

Announcing the Jena User Conference

2005-11-07T12:06:00.000Z

We're announcing the first Jena User Conference, May 10th-11th, 2006 in Bristol. There's a call for submissions to the conference. We're hoping to get a good mixture of presentations from the Jena team and presentations, demos and the like from Jena users and other researchers.

del.icio.us: jena, conference, rdf, owl, semanticweb.

technorati: jena, conference, rdf, owl, semanticweb.

Jena community IRC

2005-10-24T11:56:00.000+01:00

As Andy announced today, we've opened an IRC channel (#jena on freenode) for Jena users to hang out and chat.

Announcing ... jena-announce!

2005-10-18T13:58:00.000+01:00

We thought that it would be a good idea to have an RSS feed for announcements of changes to the Jena semantic web platform, and other project news. So here it is!

Technorati: jena, semantic-web